99% of the time, there is an underlying issue why the spark plug gets fouled out in the first place, or just plain operator error. I have used many different plug manufacturers over the years and every once in a great while any manufacturers plug will take a crap and stop sparking for no apparent reason. They all do it, not just Champion. Resistors crap out, porcelin cracks, it can happen with any.
The only thing I will say is the quality build of a NGK plug is usually better than a Champion, the Champions often where the bridge and electrode meet they are quite often off center where as a NGK is usually lined up perfectly or darn close. But sometimes that has to do with NGK and their packageing with the nice little sleeve they put in the box, just incase its dropped.